Revision b5861e5cf2fcf83031ea3e26b0a69d887adf7d21 authored by Liran Alon on 03 September 2018, 12:20:22 UTC, committed by Radim Krčmář on 07 September 2018, 16:38:42 UTC
Consider the case L1 had a IRQ/NMI event until it executed
VMLAUNCH/VMRESUME which wasn't delivered because it was disallowed
(e.g. interrupts disabled). When L1 executes VMLAUNCH/VMRESUME,
L0 needs to evaluate if this pending event should cause an exit from
L2 to L1 or delivered directly to L2 (e.g. In case L1 don't intercept
EXTERNAL_INTERRUPT).

Usually this would be handled by L0 requesting a IRQ/NMI window
by setting VMCS accordingly. However, this setting was done on
VMCS01 and now VMCS02 is active instead. Thus, when L1 executes
VMLAUNCH/VMRESUME we force L0 to perform pending event evaluation by
requesting a KVM_REQ_EVENT.

Note that above scenario exists when L1 KVM is about to enter L2 but
requests an "immediate-exit". As in this case, L1 will
disable-interrupts and then send a self-IPI before entering L2.

Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com>
Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
1 parent 564ad0a
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active_mm.rst -rw-r--r-- 3.8 KB
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cleancache.rst -rw-r--r-- 14.0 KB
conf.py -rw-r--r-- 236 bytes
frontswap.rst -rw-r--r-- 15.1 KB
highmem.rst -rw-r--r-- 5.4 KB
hmm.rst -rw-r--r-- 18.3 KB
hugetlbfs_reserv.rst -rw-r--r-- 28.8 KB
hwpoison.rst -rw-r--r-- 6.0 KB
index.rst -rw-r--r-- 1014 bytes
ksm.rst -rw-r--r-- 3.4 KB
mmu_notifier.rst -rw-r--r-- 4.1 KB
numa.rst -rw-r--r-- 8.6 KB
overcommit-accounting.rst -rw-r--r-- 2.6 KB
page_frags.rst -rw-r--r-- 2.3 KB
page_migration.rst -rw-r--r-- 11.6 KB
page_owner.rst -rw-r--r-- 3.8 KB
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